Anna Pla

Transition Metals in Organic Synthesis.

Contact info:
Dr. Anna Pla
anna.plaq@udg.edu
Tel. (+34) 972 41 82 75
Website

Grup-Anna-Roglans

Selected publications


A. Artigas, A. Pla-Quintana, A. Lledó, A. Roglans, M. Solà
Expeditious preparation of open-cage fullerenes by rhodium(I)-catalyzed [2+2+2] cycloaddition of diynes and C60: an experimental and theoretical study.
Chemistry – A European Journal, 2018, 24, 10653-10661.
DOI: 10.1002/chem.201802298

D. Cassú, T. Parella, M. Solà, A. Pla-Quintana, A. Roglans
Rhodium-catalysed [2+2+2] cycloaddition reactions of linear allene-ene-ynes to afford fused tricyclic scaffolds. Insights into the mechanism
Chemistry – A European Journal, 2017, 23, 14889-14899.
DOI: 10.1002/chem.201703194

E. Haraburda, M. Fernández, A. Gifreu, J. Garcia, T. Parella, A. Pla-Quintana, A. Roglans
Chiral induction in intramolecular rhodium-catalyzed [2+2+2] cycloadditions of optically active allene-ene/yne-allene substrates
Advanced Synthesis & Catalysis, 2017, 359, 506-512.
DOI: 10.1002/adsc.201600613

Ò. Torres, A. Roglans, A. Pla-Quintana
An enantioselective cascade cyclopropanation reaction catalyzed by rhodium(I): asymmetric synthesis of vinylcyclopropanes
Advanced Synthesis and Catalysis, 2016, 358, 3512-3516.
DOI: 10.1039/c5cs00535c

A.Lledó, A. Pla-Quintana, A. Roglans
Allenes, versatile unsaturated motifs in transition-metal-catalysed [2+2+2] cycloaddition reactions
Chemical Society Reviews, 2016, 45, 2010-2023
DOI: 10.1039/c5cs00535c

+ Publications

Dr. Anna Pla

Research overview

The construction and synthesis of molecular architectures with a high level of complexity and high added value starting from simple products is an important challenge in organic chemistry. Transition-metal catalyzed cyclizations are highly efficient and atom-economical processes that make it possible to access a wide range of carbo- and heterocyclic compounds. Our contribution to this field is based on the study of rhodium-catalyzed [2+2+2] cycloadditions with special emphasis on involving unsaturations, which permit the enantioselective generation of cycloadducts with asymmetric quaternary carbons. Furthermore, we are exploring the use of this methodology for the functionalization of molecular materials for biological, optical and electronic devices. Our aim is also to improve these catalytic processes through a synergy of experimental work and theoretical calculations taking advantage of our membership of the IQCC and our collaboration with Prof. Miquel Solà. We also undertake experimental mechanistic studies intercepting reactive intermediates by electrospray ionization mass spectrometry (ESI-MS).

The use of alkenes and allenes as highly versatile substrates in cyclizations to create chiral polycyclic compounds

The involvement of alkenes and allenes in transition-metal calalyzed [2+2+2] cycloaddition reactions has the advantage of allowing for the eventual introduction of stereogenic centres in the newly formed six-membered ring and of affording complex polycyclic scaffolds. Our work is focused on the use of properly substituted alkenes, which are more reluctant to react than alkynes, that allow the synthesis of chiral cyclohexadienes and their further functionalization by Diels-Alder reaction. We are also investigating the use of allenes, unsaturated substrates that are more reactive than alkenes and that deliver cycloadducts with an exocyclic double bond that can subsequently be manipulated. One of the main aims in our research is to control the chemoselectivity and regioselectivity of these processes by determining the factors that govern them both experimentally and theoretically.

The functionalisation of fullerenes by cycloaddition reactions to provide a variety of potential molecular materials for biological, optical and electronic devices

Fullerenes are a class of molecule made up of carbon atoms with an unusual hybridization (sp2,3) exhibiting a chemical reactivity similar to that of electron-deficient olefins. [60]Fullerene, in particular, has received considerable attention due to its interesting spherical structures and unique physical and chemical properties. The functionalization of [60]fullerene with different functional groups provides a variety of potential molecular materials for biological, optical, and electronic devices. Our work is focused on exploring the versatility of rhodium complexes in the cycloaddition of pi-unsaturations to C60 as a tool to functionalize these molecules in a straightforward manner.

AnnaRoglans_RL_2

Mechanistic studies of transition-metal catalyzed reactions through electrospray ionization mass spectrometry (ESI-MS)

In order to effectively control and improve the catalytic reactions, it is necessary to understand the mechanistic details of the process. One of the difficulties faced in these investigations is that the low concentrations and transient nature of most of the intermediates involved make their identification difficult. Therefore, techniques that allow the direct monitoring of these reactive intermediates are of great interest. One of our research lines is to use electrospray ionization mass spectrometry (ESI-MS) and subsequent MS/MS analysis to obtain detailed data by trapping and identifying short-lived intermediates in transition-metal catalyzed [2+2+2] cycloaddition reactions. In addition to observing the molecular mass of ions for many reactive intermediates, this technique reveals structural information through characteristic fragmentation patterns by collision-induced dissociation. All these data help us to more fully understand the course of cycloadditions and allow us to improve these reactions.

AnnaRoglans_RL_3

Methodological studies of cyclizations through rhodium carbenoid intermediates generated from tosylhydrazones

Research line led by Dr. Anna Pla-Quintana

The vast majority of syntheses rely on step-by-step transformations. This is an inefficient, time-consuming strategy that would be greatly improved by the implementation of effective cascade processes. Of the many intermediates that can initiate or participate in cascade processes, metal-carbenoids are an excellent option due to their versatility and high reactivity. Rhodium(II) dimers have emerged as the most versatile class of complexes for single-step carbenoid mediated reactions. The transition-metal carbenoids that are required for these reactions are mostly prepared from nitrogen extrusion of diazo compounds that have non-negligible security and toxicity risks. Furthermore, the methodology is limited just to carbenoids with certain electronic properties. This research line is aimed at preparing rhodium carbenoids making use of rhodium(I) complexes to decompose arylsulfonylhydrazones, a carbenoid source that is much safer and easier to handle and which is amenable to all types of carbenoids. Rhodium(I) complexes with atropoisomeric ligands are chosen to exploit their versatility and stereoselectivity in cycloaddition reactions, nucleophilic substitutions and rearrangements. This combination is selected to trigger cascade reactions that allow the straightforward enantioselective synthesis of (poly)cyclic compounds from readily available linear starting materials.

AnnaRoglans_RL_3

People

Principal Investigator

Anna Pla


Staff and Postdocs

Anna Roglans

Professor


PhD and MACMoM students

Albert Artigas

PhD student (FPI)

Supervisor:
- A. Lledó
- A. Roglans
- M. Solà

Jordi Vila Vadri

PhD Student (FI)

Supervisor:
- Anna Roglans
- Anna Pla

Àlex Díaz

MACMOM Student

Supervisor:
- Anna Pla
- Anna Roglans


Funding

MINECO Projects. Proyectos I+D.

Project: Estudios teorico-experimentales de ciclaciones catalizadas por metales de transición. Nuevos desarrollos en aromaticidad, funcionales de la densidad y química supramolecular (CICATMET)
Researcher: Dr Miquel Solà & Dr Anna Roglans
Reference: CTQ2014-54306-P
Funding: 196.020 €
Periode: 2015 – 2017

News

IQCC Science Slam, May 11, 2018

In 2015 and 2016, the IQCC organized for the first and the second time the Science

Albert Artigas wins second prize in “your thesis in 4 minutes” contest

On 22ndMay 2018, Albert Artigas, a PhD researcher of the Institute of Computational

ChemEurJ cover on C60 opening using Rh-catalyst

Albert Artigas, Anna Pla-Quintana, Agustí Lledó, Anna Roglans, and Miquel Solà, members of